I'm looking at digging a Japanese maple about 2.5 -3 meters tall and older tree of about 6-7 years old.

A few questions before i commit.

1. How hard / extensive are the root systems of a tree of this size is it to dig out?2. Can the roots be hard pruned to make it more manageble?3. I know perhaps the best time to pull one would most likely be July middle of winter but is it too early to be digging?

In digging any large Japanese maple i would first of all i would be waiting until mid-winter just to be safe. if it is 6-7 years old then it is likely that you can dig it out all in one go, but below is my approach for digging older trees.

Firstly before making any commitments i would expose the root system to see just what i'm dealing with. It may be the case that if it has some very thick roots it would be safer to dig it over the course of two or three years instead of trying to do it all in one year. In that case i would cut half the thick roots on one side, then bury again and allow new roots to grow for a season, then cut the other half of the roots the following winter and either remove it entirely at the time or allow it one more year in the ground to recover before finally digging it out. That way the shock is spread over time rather than one big shock in one go which can be lethal to established trees. This likely won't apply to your tree and may be more applicable to a tree that has been in the ground for 15-20 years for example.

Japanese Maple can tolerate some quite severe root work though i like to play it safe and not cut back any harder than about 30% just to give a safety margin.

I know Tim's cautious approach allows a little more safety margin but few of us have 2-3 years to collect a tree. I have found JM reasonably tolerant of root pruning so I would make the attempt in one go on the understanding that JM, in particular, are prone to parts of the trunk dying when roots and trunk are cut back hard in one go.

Leaf fall is the start of the digging season for deciduous trees. If you think about it, bare rooted trees will be in the nurseries in a couple of weeks. Where did the come from? Commercial suppliers field grow the stock then dig them as soon as the leaves drop so they can get them to the retailers as soon as possible. Those bare rooted trees have almost 100% survival so early winter must be safe to transplant.

The root system will depend on a lot of factors but you will probably find at least a few larger roots under your tree. Maple roots are VERY hard. I have not been able to cut any roots that are thicker than 2cm with a shovel. Large loppers will cut roots up to 2-3 cm. For any that are thicker you will need a saw or very sharp axe. You will probably find that you will need to dig quite a large hole so you can get under the root ball and get at the larger ones that are growing straight down.

Before proceeding consider how large a pot you will need for this tree. I find that most trees I collect will not fit into a container that is less than 4 times the diameter of the trunk. I have noticed that tree trunks seem to expand quite a bit between digging and potting so the container needed is usually quite a bit bigger than the one you had planned on A thick trunk may look attractive but most will need substantial cutting and end up as just a thick stump which can take many years to grow back and produce anything even vaguely bonsai.

I should have included this will be going from landscape tree to landscape tree so the only root pruning would be for transport / ability to fit it in it's new location.

It's potentially coming from someone's garden looks health enough hence why i can't dig it over multiple years and timing might only be in the next few weeks.I'm assuming i may need to use a chainsaw to cut some of the larger roots?

Not sure on the price that will have to come down but japanese maples of this size are few and far between here.

In that case of it going from landscape tree to landscape tree see if the seller will allow you to dig it mid winter and try to take as much roots as you reasonably can. If you have to dig it now just really take as much roots as you can and cross your fingers

Last edited by TimS on May 22nd, 2018, 7:16 pm, edited 1 time in total.

Not sure how hard the ground will be but the roots should be a bit thinner away from the trunk so easier to cut. Chainsaws do not like soil and grit. A handsaw or axe would probably be better but if you have the chainsaw and a chain you don't need any more...Getting under the rootball to cut vertical roots will be one issue. You will still need to dig quite a large hole so you can tunnel underneath to get those ones. Rock the trunk as you go. That will show where the remaining roots are. Towards the end you may be able to swing the trunk enough to break the last few roots - a few broken roots will not matter and you can probably cut them clean after it is out of the hole.Weight is another issue. The tree will probably weigh 50kg or more. With soil on the roots it will probably be 2-3 times that. I personally like to shake off as much soil as I can at the dig site. Makes the tree more manageable and does not compromise the health. Just water the remaining roots on site if possible and cover them for the trip home. It does not seem to matter if roots dry out a bit for a couple of hours.Trimming the top will reduce weight and bulk and make it a bit easier to move and transport. Look for obvious places to reduce the top - take out entire crowded branches or any that are growing into the centre, crossing through the canopy, etc as well as trimming smaller bits near the top. JM usually come back readily, even from older bare wood.Phil's point about having the new hole dug at home before is good. The tree can go in quicker when you get back.

Sorry for the late reply i've been busy renovating hence also beginning to plan the garden side of things....japanese of course

Someone beat me to the punch i've messaged the gentleman so it might be still happening if the buyer falls through.That said the awesome information here will help me in the coming months as its just matter of if and not when i do this.